After the state of New York instituted a policy in 2006 that excluded patients with cardiogenic shock from publicly disclosed risk-adjusted mortality rates, the rates of PCI for patients with acute MI and cardiogenic shock increased significantly, according to a database analysis.

Lead researcher James M. McCabe, MD, of the University of Washington, and colleagues published their results online in JAMA Cardiology on July 27.

In 1992, New York became the first state to publicly report in-hospital, risk-adjusted mortality after PCI. Since then, Massachusetts, Pennsylvania, Washington and other states have implemented similar policies. The researchers noted that the rules are intended to improve the quality of care, but they may also lead to physicians choosing not to perform PCIs on higher-risk patients. That concern caused New York to exclude patients with refractory cardiogenic shock from PCI analyses starting on Jan. 1, 2006.

For this study, the researchers evaluated the state hospitalization databases of New York, Massachusetts, Michigan and New Jersey from 2002 through 2012, as well as California from 2003, through 2011.

Hospitals in California, Michigan and New Jersey do not publicly report risk-adjusted mortality, while Massachusetts does not exclude patients with cardiogenic shock from its reporting. The researchers wanted to compare the rates of PCI and surviving to discharge differed between New York and the other states.

Of the 45,977 patients with acute MI and cardiogenic shock, 47.8 percent underwent PCI. The mean age was 69.7 years old, and 39.5 percent of patients were female.

After the researchers adjusted for patient factors, they found that operators in New York were 28 percent more likely to perform PCI on patients with acute MI and cardiogenic shock following the public reporting policy changes. During that same time period, operators in the other states were 9 percent more likely to perform PCIs in the same high-risk patient group.

In New York, the use of coronary angiography significantly increased from the initial period (2002 to 2005) to the period following the policy changes (2006 to 2012). Meanwhile, there was a significant decrease in the rates of in-hospital death and no change in the rates of CABG.

“This increase in the use of PCI for cardiogenic shock was significantly greater than that observed during the same period in several comparator states,” the researchers wrote. “These data may suggest that the policy changes implemented in the New York public reporting process had the desired effect of reducing risk aversion. Concomitantly, the in-hospital mortality of all patients with [acute MI] and cardiogenic shock decreased to a significantly greater degree in New York than in the comparator states during the intervals analyzed, suggesting that the public reporting policy change may have also improved public health by facilitating more revascularization, a guideline-directed therapy for cardiogenic shock.”

They also noted that at the beginning of the study period, New York had significantly lower rates of coronary revascularization and worse rates of in-hospital death for acute MI and cardiogenic shock. By the end of the study, New York also had lower rates of coronary revascularization for acute MI with cardiogenic shock.

“These findings, in addition to lower observed rates of coronary revascularization and higher rates of CABG in New York compared with the comparator states before and after the policy change, could be indicative of continued risk aversion on the part of PCI operators in a public reporting environment,” the researchers wrote.

The researchers mentioned a few potential limitations of their analysis, including that they identified patients in administrative databases and used claims-based data when adjusting for the severity of illness. They also could not establish causality in this study.

“The present analysis suggests that the censoring of adjudicated, extreme-risk cases may have been effective at facilitating guideline-directed revascularization and improving outcomes,” the researchers wrote. “Further research is required to better understand how to balance the desires for health care transparency with a system that encourages appropriate care for the highest-risk patients.”